George: Throughout the 1980s and early 1990s, hardly anyone learned ballroom dancing. ███ ██ ██ ████ █ █████ ██████ ██ ██████ ███ ████ ████████ ███████ ████████
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George asks why a large number of people are now taking ballroom dancing lessons, even though in the 1980s and 1990s, almost nobody took ballroom dancing lessons.
Boris’s answer is that in 1995, lots of people learned some ballroom dances, and this lead to other ballroom dances becoming popular.
George isn’t just asking “Why are lots of people taking ballroom dancing lessons?” He’s asking why so many people are taking ballroom dancing in light of the fact that it was unpopular in the past. In other words, George sees a discrepancy that needs to be explained.
Boris’s answer doesn’t help resolve the discrepancy. Pointing out that ballroom dancing started to become popular in 1995 doesn’t explain WHY it became more popular after a period of being unpopular.
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